Tabs and Indents

When the check box is cleared, IntelliJ IDEA uses spaces instead of tabs.

Smart tabs

If this check box is selected, IntelliJ IDEA inserts tabs for indentation and reformatting,
but fine alignment to a necessary column is done
only via spaces without replacing them with tabs.
This is done in order to preserve visual
representation of the source code, when the
Tab Size
is changed.

If this check box is cleared, only tabs are used. This means that a group of spaces that fits the specified tab size is automatically replaced with a tab,
which may result in breaking fine alignment.

The Smart Tabs check box is available if the Use Tab Character
check box is selected.

Tab size

In this text box, specify the number of spaces included in a tab.

Indent

In this text box, specify the number of spaces (or tabs if the
Use Tab Character
check box is selected) to be inserted for each indent level.

Continuation indent

In this text box, specify the number of spaces (or tabs if the
Use Tab Character check box is selected) to be inserted at the next line in case of a construct break.

Keep indents on empty lines

If this check box is selected, then IntelliJ IDEA will keep indents on the empty lines as if they have contained some code.
If this check box is not selected, IntelliJ IDEA will delete the tabulation characters.

Set From

Click this link to reveal the list of languages to be used as the base for the current language code style. So doing,
only the settings that are applicable to the current language are taken. All the other settings are not affected.

This link appears in the upper-right corner of the language-specific code style page, when applicable.

Click Reset to discard changes and return to the initial set of code style settings.